[ 521 ] 
and diluted with water to the fame volume of the 
other. 
This laft took i lb 3 5 of acid of vitriol, diluted 
with water, to be faturated, and did not grow hot; 
wheras the water containing the four ounces of al- 
kaline vapours took up 2 lb 35 of the fame acid of 
vitriol, and grew fo very hot, that the veffel could 
fcarce be held in the hand, even after having been 
diluted at different times with two quarts of water. 
This fhews that there is a great difference in the 
two, and that it is not intirely owing to ftrength. 
The heat produced by the vapours paffmg through 
the water, was tried at another diftillation, and 
raifed the quickfilver in Fahrenheit’s thermometer 
to 1 10 degrees. 
In rectifying cauftic volatile alkaly with lime, 
there is likewife a very great quantity of elaftic air 
fet free, highly charged with volatile alkaly, which 
condenfes in water and heats it. 
Water may be fo ft rongly charged with this vapour, 
that it will make very ftrong Eau de luce, nay, much 
ftronger than that which we laid before was diftilled 
and let apart for Eau de luce : but it is neceffary, 
as mentioned before, to make ufe of two done bot- 
tles, changing them as often as they grow warm. 
Experiment II. 
On the diftillation of the acid of fait by means 
of the acid of vitriol ; for the apparatus fee fig. 2. 
* A green quart retort coated with loam was 
made ufe of for this experiment, and it was placed 
* What goes by the name of a quart retort holds better than 
two gallons of water. 
Vol. LVII. x x X 
HI 
